//CacheImage
if(document.images) {
	
	naviOn = new Array();
	naviOver = new Array();
	naviOff = new Array();
	
	
	//home
	naviOn[1] = new Image();
	naviOn[1].src = "/img/btn_home_on.gif";
	
	naviOver[1] = new Image();
	naviOver[1].src = "/img/btn_home_over.gif";
	
	naviOff[1] = new Image();
	naviOff[1].src = "/img/btn_home_off.gif";
	
	//what
	naviOn[2] = new Image();
	naviOn[2].src = "/img/btn_what_on.gif";
	
	naviOver[2] = new Image();
	naviOver[2].src = "/img/btn_what_over.gif";
	
	naviOff[2] = new Image();
	naviOff[2].src = "/img/btn_what_off.gif";
	
	//art
	naviOn[3] = new Image();
	naviOn[3].src = "/img/btn_art_on.gif";
	
	naviOver[3] = new Image();
	naviOver[3].src = "/img/btn_art_over.gif";
	
	naviOff[3] = new Image();
	naviOff[3].src = "/img/btn_art_off.gif";
	
	//gallery
	naviOn[4] = new Image();
	naviOn[4].src = "/img/btn_gallery_on.gif";
	
	naviOver[4] = new Image();
	naviOver[4].src = "/img/btn_gallery_over.gif";
	
	naviOff[4] = new Image();
	naviOff[4].src = "/img/btn_gallery_off.gif";
	
	//shop
	naviOn[5] = new Image();
	naviOn[5].src ="/img/btn_shop_on.gif";
	
	naviOver[5] = new Image();
	naviOver[5].src = "/img/btn_shop_over.gif";
	
	naviOff[5] = new Image();
	naviOff[5].src = "/img/btn_shop_off.gif";
	
	//museum
	naviOn[6] = new Image();
	naviOn[6].src = "/img/btn_museum_on.gif";
	
	naviOver[6] = new Image();
	naviOver[6].src = "/img/btn_museum_over.gif";
	
	naviOff[6] = new Image();
	naviOff[6].src = "/img/btn_museum_off.gif";
	
	//media
	naviOn[7] = new Image();
	naviOn[7].src = "/img/btn_media_on.gif";
	
	naviOver[7] = new Image();
	naviOver[7].src = "/img/btn_media_over.gif";
	
	naviOff[7] = new Image();
	naviOff[7].src = "/img/btn_media_off.gif";
	
	//touch
	naviOn[8] = new Image();
	naviOn[8].src = "/img/btn_touch_on.gif";
	
	naviOver[8] = new Image();
	naviOver[8].src = "/img/btn_touch_over.gif";
	
	naviOff[8] = new Image();
	naviOff[8].src = "/img/btn_touch_off.gif";
	
	//exhibition
	naviOn[9] = new Image();
	naviOn[9].src = "/img/btn_exhibition_on.gif";
	
	naviOver[9] = new Image();
	naviOver[9].src = "/img/btn_exhibition_over.gif";
	
	naviOff[9] = new Image();
	naviOff[9].src = "/img/btn_exhibition_off.gif";
	
	//inquiry
	naviOn[10] = new Image();
	naviOn[10].src = "/img/btn_inquiry_on.gif";
	
	naviOver[10] = new Image();
	naviOver[10].src = "/img/btn_inquiry_over.gif";
	
	naviOff[10] = new Image();
	naviOff[10].src = "/img/btn_inquiry_off.gif";
	
}

//changeImage
function imgChange(imgName,imgState,imgNum) {
	if(document.images) {
		if(document[imgName].src.indexOf("_on") <= 0){
			document[imgName].src = eval(imgState)[imgNum].src;
		}
	}
}